Solvent control of structural type: three different structures from the reaction of a dimeric copper complex with lanthanum nitrate in three different solvents

Abstract

The reaction of a dimeric copper complex, [Cu₂L₄]1(L = C₅H₃CINO^–, the anion of 6-chloro-2-hydroxypyridine), with hydrated lanthanum nitrate has been studied. The crystalline products are determined by the solvent used. If the reaction is carried out in a mixture of methanol–dichloromethane a compound of stoichiometry [Cu₃LaL₅(NO₃)(OMe)(MeOH)₂]·1.5MeOH·0.5Et₂O 2 is isolated. If the reaction is carried out in ethanol–dichloromethane a compound of stoichiometry [Cu₃LaL₈(NO₃)(EtOH)]·0.5Et₂O 3 is found. If acetonitrile–dichloromethane is used the complex [Cu₂La₂L₈(HL)₂(NO₃)₂]·2HL·2MeCN 4 can be crystallised. All of these compounds have been characterised by X-ray crystallography and the unusual structures are described.